The SAP S&D 2-Tier benchmark has always been one of my favorites. This is probably the most real world benchmark of all server benchmarks done by the vendors. It is a full blown application living on top of a heavy relational database. And don't forget that SAP is one of the most successful software companies out there, the undisputed market leader of Enterprise Resource Planning.

SAP is thus an application that misses the L2 cache much more than most applications out there, with the exception of some exotic HPC apps. We made an in depth profile of SAP S&D, but here is the summary:

The application has very low instruction level parallelism (ILP) and as a result is not taxing the integer units much (IPC = 0.3-0.55, SPECint 2006: >1) .

SAP misses the L2 cache much more than most applications out there (4 to 10 times more than SPECint2006 apps)

The application has a relatively large but "prefetcheable" instruction footprint, which allows the prefetchers to reduce the instruction related cache misses

The application has a massive and random data footprint, putting great pressure on the load subsystem. As a result the out of order engine has to hide the latency the best it can, and large ROB and load buffers help a lot. The latency of the memory subsystem matters.

The new Opteron does not boost SAP performance. A 6% clock increase translates into a 5% performance increase. As we discussed previously, SAP is one of the few complex server applications where the "Interlagos" Opteron performs a lot better than its predecessor. The application does not seem to benefit from any of the small improvements that the Piledrive core offers. Or maybe HP's benchmark team did not spend much time on this particular benchmark. Since the HP score is the only Interlagos score available, we have no other option than to wonder which of the two options is the closest to the truth.

Not that it matters much: the best SAP servers are Xeon E5 based. In this market of expensive consulting and software, $500 dollar savings on hardware is peanuts. So people tend to go for the best performance, and the Xeon E5 are clearly better at delivering raw SAP performance.

Post Your Comment

55 Comments

I have dual Opteron 6344 workstation system, which tends to be either near complete idle or near complete busy, so C states are extremely important to me. The CPU has power sensors that are exposed in Linux using the 'sensors' tool. With C6 enabled, I get the power consumption per socket down to 42 Watts, which still seems like a lot, but disabling C6 made it jump to 104W per socket, when under 100% load it is constantly within 1W of the 115W TDP limit.I did not see a significant impact of C1E, neither with C6 enabled nor disabled, presumably because I rarely have cores that are idle for a short period.More annoying to me is the lack of S3 suspend mode, the system still consumes around 100W on S1.Reply

I've been abandoning tech sites due to stupid posters and internet trolls.There is so much addition info and questions in the comments and I don't know why are you letting people ruin that feature from your site?You should make a ranking system(similar to /. ) for users, in order to automatically hide someone's comments, so we don't have to double check every time the poster and/or the comment.

I feel stupid for making that type of comment, also reading specific stupid opinions, below that article.Reply

I like your ideas, however most of the laugh (or should I say cringe?) worthy comments would be hidden and the entertainment value would be tainted by having to click the Show button all the time. ;)Reply

I had meetings and people visiting me, so I could not "baby sit" the reactions. But if you don't react to the offensive message we can delete them. So the best way to deal with th trolls is to ignore. Sooner or later, they will be banned. Reply